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toMap :: HashSet a -> HashMap a ()

rio RIO.HashSet

Convert to set to the equivalent HashMap with () values.
```
>>> HashSet.toMap (HashSet.singleton 1)
fromList [(1,())]
```
concatMap :: Foldable t => (a -> [b]) -> t a -> [b]

rio RIO.List

Map a function over all the elements of a container and concatenate the resulting lists.
Examples
Basic usage:
```
>>> concatMap (take 3) [[1..], [10..], [100..], [1000..]]
[1,2,3,10,11,12,100,101,102,1000,1001,1002]
```
```
>>> concatMap (take 3) (Just [1..])
[1,2,3]
```
foldMapWithKey :: Monoid m => (k -> a -> m) -> Map k a -> m

rio RIO.Map

Fold the keys and values in the map using the given monoid, such that
```
foldMapWithKey f = fold . mapWithKey f
```
This can be an asymptotically faster than foldrWithKey or foldlWithKey for some monoids.
isProperSubmapOf :: (Ord k, Eq a) => Map k a -> Map k a -> Bool

rio RIO.Map

Is this a proper submap? (ie. a submap but not equal). Defined as (isProperSubmapOf = isProperSubmapOfBy (==)).
isProperSubmapOfBy :: Ord k => (a -> b -> Bool) -> Map k a -> Map k b -> Bool

rio RIO.Map

Is this a proper submap? (ie. a submap but not equal). The expression (isProperSubmapOfBy f m1 m2) returns True when keys m1 and keys m2 are not equal, all keys in m1 are in m2, and when f returns True when applied to their respective values. For example, the following expressions are all True:
```
isProperSubmapOfBy (==) (fromList [(1,1)]) (fromList [(1,1),(2,2)])
isProperSubmapOfBy (<=) (fromList [(1,1)]) (fromList [(1,1),(2,2)])
```
But the following are all False:
```
isProperSubmapOfBy (==) (fromList [(1,1),(2,2)]) (fromList [(1,1),(2,2)])
isProperSubmapOfBy (==) (fromList [(1,1),(2,2)]) (fromList [(1,1)])
isProperSubmapOfBy (<)  (fromList [(1,1)])       (fromList [(1,1),(2,2)])
```
isSubmapOf :: (Ord k, Eq a) => Map k a -> Map k a -> Bool

rio RIO.Map

This function is defined as (isSubmapOf = isSubmapOfBy (==)).

rio	RIO.HashSet

rio	RIO.List

isSubmapOfBy :: Ord k => (a -> b -> Bool) -> Map k a -> Map k b -> Bool

rio	RIO.Map

The expression (isSubmapOfBy f t1 t2) returns True if all keys in t1 are in tree t2, and when f returns True when applied to their respective values. For example, the following expressions are all True:

isSubmapOfBy (==) (fromList [('a',1)]) (fromList [('a',1),('b',2)])
isSubmapOfBy (<=) (fromList [('a',1)]) (fromList [('a',1),('b',2)])
isSubmapOfBy (==) (fromList [('a',1),('b',2)]) (fromList [('a',1),('b',2)])

But the following are all False:

isSubmapOfBy (==) (fromList [('a',2)]) (fromList [('a',1),('b',2)])
isSubmapOfBy (<)  (fromList [('a',1)]) (fromList [('a',1),('b',2)])
isSubmapOfBy (==) (fromList [('a',1),('b',2)]) (fromList [('a',1)])

Note that isSubmapOfBy (_ _ -> True) m1 m2 tests whether all the keys in m1 are also keys in m2.

biconcatMap :: Bifoldable t => (a -> [c]) -> (b -> [c]) -> t a b -> [c]

rio RIO.Prelude

Given a means of mapping the elements of a structure to lists, computes the concatenation of all such lists in order.
Examples
Basic usage:
```
>>> biconcatMap (take 3) (fmap digitToInt) ([1..], "89")
[1,2,3,8,9]
```
```
>>> biconcatMap (take 3) (fmap digitToInt) (Left [1..])
[1,2,3]
```
```
>>> biconcatMap (take 3) (fmap digitToInt) (Right "89")
[8,9]
```

bifoldMap :: (Bifoldable p, Monoid m) => (a -> m) -> (b -> m) -> p a b -> m

rio	RIO.Prelude

Combines the elements of a structure, given ways of mapping them to a common monoid.

bifoldMap f g ≡ bifoldr (mappend . f) (mappend . g) mempty

Examples

Basic usage:

>>> bifoldMap (take 3) (fmap digitToInt) ([1..], "89")
[1,2,3,8,9]

>>> bifoldMap (take 3) (fmap digitToInt) (Left [1..])
[1,2,3]

>>> bifoldMap (take 3) (fmap digitToInt) (Right "89")
[8,9]

bimap :: Bifunctor p => (a -> b) -> (c -> d) -> p a c -> p b d

rio	RIO.Prelude

Map over both arguments at the same time.

bimap f g ≡ first f . second g

Examples

>>> bimap toUpper (+1) ('j', 3)
('J',4)

>>> bimap toUpper (+1) (Left 'j')
Left 'J'

>>> bimap toUpper (+1) (Right 3)
Right 4

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